Load fuses for electric power lines



March 22, 1955 L R 2,704,795

LOAD FUSES FOR ELECTRIC POWER LINES Filed Jan. 25, 1954 Mimi lllllw 4O INVENTOR.

. WILLARD E. MILLER ATTORNEYS United States Patent LOAD FUSES FOR ELECTRIC POWER LINES Willard E. Miller, Dexter, Oreg.

Application January 25, 1954, Serial No. 405,754

1 Claim. (Cl. 200-117) My invention relates to load fuses for electric power lines and is particularly adapted for fusing transformers.

The primary object of my invention is the method of adapting standard pin type insulators to the fuse assembly. Heretofore specially constructed insulators were used in the fuse assembly, which were expensive to replace and not always available, but with my new and improved fuse the standard pin type insulator can be used, substantially reducing repair costs of the fuses.

These and other incidental objects will be apparent in the drawings, specification and claim.

Referring to the drawings:

Figure 1 is a fragmentary side view of a power pole, including its cross arms, power line, transformer and one of my improved fuses mounted to the cross arm, parts broken away for convenience of illustration.

Figure 2 is a sectional view, illustrating the mounting of a pin insulator to my new and improved insulator mounting. This view is taken on line 2-2 of Figure 1.

Figure 3 is a fragmentary plan view of one of the fuse supporting arms, taken on line 3-3 of Figure 1.

Figure 4 is a plan partially broken away view of the fuse tension arm.

Figure 5 is an exploded view of one of the mounting elements for supporting the insulators and fuse assembly.

Referring more specifically to the drawings:

I illustrate a fragmentary portion of a power line pole 1 with the usual cross arms 2 secured thereto. The power line 3 is affixed to the pin insulator 4 in the usual manner. A transformer 5 is secured to the pole 1 by the usual means. I have broken away sections of the pole for convenience of illustration.

My invention resides in the fuse assembly A mounted to the cross arm 2 by the bracket 6. I employ a pair of pin type insulators 7 and 8; The insulator 8 is secured to the bracket arm 6 in the following manner. A metallic insulating pin 9 passes through a hole 10 within the bracket 6 and is threaded into the member 11. The same is locked thereto by the locking nut 12. The upper end of the insulator 8 has a transverse trough or groove 13 formed therein into which the member 11 nests, as best illustrated in Figure 2.

The member 11 is secured to the top of the insulator 8 by the two-piece collar 14 which has oppositely disposed ears 15 forming part thereof to which the cars 16 of the member 11 are secured by bolts 17. By constructing the collar 14 in half sections 18 and 19, bolted together by bolts 20A extending through the ears 20, the same can be readily adapted to the annular groove 21 of the insulator, as best illustrated in Figures 1 and 2. The insulator 7 is threaded to the pin 9 at 22 in the usual manner.

The upper fuse holding arm 23 has a demountable clamp 24 formed on one of its ends, which is adapted to encircle the groove 25 of the insulator 7, as best illustrated in Figure l. The opposite end of the arm 23 has a double bifurcated end 26 with sockets 27 for receiving the upper end 28 of the fuse 29. This is of usual structure.

Threaded into the insulator 8 at 30 is a pin 31, having threads 32 on its lower end. A double spring fuse arm 33 is clamped to the lower end of this pin by way of the clamps 34. The lower clamp 35 is threaded to the threads 32 of the pin 31, while the upper clamping washer 35A is brought down against the spring wire arms 36 extending from the coil 37 and locked thereagainst by the locking nut 38. The lower end 39 of the fuse 29 is threaded into the loops 40 of the fuse arm 33, as best illustrated in Figures 1 and 4, the arm 33 keeping the fuse 29 under tension at all times.

The usual connection 41 connects the power line 3 to the arm 23, while the usual conductor 42 connects the lower arm 33 of the fuse to the transformer 5 by way of the usual fitting 43 and insulator 44.

In operation, electrical energy fiows from the main line 3, Figure 1, through the conductor 41, into the fuse arm 23, fuse 29, the tension fuse arm 33, conductor 42 and into the transformer 5. In the event of an overload the fuse 29 will give way under the pull of the arm 33 caused by its spn'ng coil 37. This will break the circuit through the main line and the transformer 5, in the event of an overload caused by the usual conditions. The fuse arm 23 and the arm 33 can be connected together by inserting a new fuse 29 by a hot stick used by line men.

As stated in the objects of my invention, the primary object of the invention is in the assemblying of the insulators 7 and 8, these insulators replacing a solid continuous insulator as is commonly used. By using the standard pin type insulator, the cost of repair is reduced many times.

What is claimed is:

A fuse supporting means comprising a pair of insulators having threaded sockets in their lower ends, a pin threaded at one end into one of said sockets, clamping means threaded on the other end of said pin and engaging the upper end of the other of said insulators, a supporting bracket secured to said pin, a second pin threaded at one end in the socket of said other insulator, an upper fuse supporting arm fixed to and extending from one of said insulators, a lower fuse suporting arm fixed to and extending from said second pin.

References Cited in the file of this patent UNITED STATES PATENTS 2,134,470 Conrad Oct. 25, 1938 2,175,328 Walsh Oct. 10, 1939 2,292,706 Mammel et a1. Aug. 11, 1942 

